package net.jeeshop.core.pay.wxpay.util;

import com.swetake.util.Qrcode;

import javax.imageio.ImageIO;
import javax.servlet.http.HttpServletResponse;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.OutputStream;

/**
 * Created by xvhuichuang on 2017/7/5.
 */
public class QrcodeUtil {

    public void encoderQRCoder(String content, HttpServletResponse response) {
        try {
            Qrcode handler = new Qrcode();
            handler.setQrcodeErrorCorrect('M');
            handler.setQrcodeEncodeMode('B');
            handler.setQrcodeVersion(7);
            byte[] contentBytes = content.getBytes("UTF-8");
            BufferedImage bufImg = new BufferedImage(140, 140, BufferedImage.TYPE_INT_RGB);
            Graphics2D gs = bufImg.createGraphics();
            gs.setBackground(Color.WHITE);
            gs.clearRect(0, 0, 140, 140);
            //设定图像颜色：BLACK
            gs.setColor(Color.BLACK);
            //设置偏移量  不设置肯能导致解析出错
            int pixoff = 2;
            //输出内容：二维码
            if (contentBytes.length > 0 && contentBytes.length < 124) {
                boolean[][] codeOut = handler.calQrcode(contentBytes);
                for (int i = 0; i < codeOut.length; i++) {
                    for (int j = 0; j < codeOut.length; j++) {
                        if (codeOut[j][i]) {
                            gs.fillRect(j * 3 + pixoff, i * 3 + pixoff, 3, 3);
                        }
                    }
                }
            } else {
                System.err.println("QRCode content bytes length = " + contentBytes.length + " not in [ 0,120 ]. ");
            }
            gs.dispose();
            bufImg.flush();
            OutputStream outputStream = response.getOutputStream();
            ImageIO.write(bufImg, "PNG", outputStream);
            outputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}
